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Advertising supplement provided by Pittsburgh Corning

Mortar joints should not be furrowed.

Expansion strips, made of dense fibrous glass, polyethylene, or mineral wood replace mortar at the jambs and head and at intermediate structural locations to allow for panel expansion and contraction.

Panel framing. Three methods for framing glass block panels are recommended to accommodate lateral support along the top and sides of each panel — panel anchor, channel, and chase systems. These supports are designed to resist the applied loads, or a minimum of 200 pounds per lineal foot of panel, whichever is greater.

Panel anchors: Panel anchors tie glass block panels into the surrounding frame at head and jamb locations. Anchors are used along the jambs and at the head, or they can be used in combinations with channel construction where one type of detailing is at the jambs and the other at the head. Anchors are normally placed a maximum of every 16 inches on center. This means that for an 8-inch block, panel anchors would be placed in every other course.

 

Scioto Downs, Columbus, OH / Architect: Kellam and Associates, Inc.

Channel framing: Either a metal channel or metal angles combined to form a channel can be used. The channel opening (for a nominal 4-inch-thick block) must be 4 1/4 inches to 4 1/2 inches wide by a minimum of 1 3/8 inches deep to allow for a 1-inch minimum recess of glass block into the channel and for placement of the expansion material inside the channel. It is critical that the channel opening be square, not tapered as in standard channels, so as not to pinch the edges of the glass block. The oversized opening allows the insertion of packing material and sealant between the recessed faces of the glass block and channel legs.

Chase method: A recessed chase can be inserted into concrete or masonry jambs and head, eliminating the need for anchors or metal channels. The dimensions described must be similar to those described above for metal channels.